While trying to figure out what my spells do, I found a use for arcane mark. Arcane Mark just puts my wizard mark on something and it lasts for a month. The use is to put an invisible tattoo on everyone in the party to thwart dopplegangers by easily identifing party members. I'll mark everyone unless someone wants to opt out by our next gaming session. Anyone not want the mark? If you think this is being paranoid, then I remind you that noodles is our DM that brought the party stone on a rope and glue pot.